Safety and Efficacy of External Beam Radiation Therapy in Hepatocellular Carcinoma Patients Previously Treated With Yttrium 90 Transarterial Radioembolization

Kanokphorn Thonglert; Joseph Tsai; Wayne L Monsky; August C Anderson; Clemens Grassberger; Stephen R Bowen; Matthew J Nyflot; Yulun He; Peter Zaki; Guy E Johnson; Smith Apisarnthanarax

doi:10.1016/j.adro.2025.101984

Safety and Efficacy of External Beam Radiation Therapy in Hepatocellular Carcinoma Patients Previously Treated With Yttrium 90 Transarterial Radioembolization

Adv Radiat Oncol. 2025 Dec 27;11(3):101984. doi: 10.1016/j.adro.2025.101984. eCollection 2026 Mar.

Authors

Affiliations

¹ Department of Radiation Oncology, University of Washington School of Medicine, Seattle, Washington.
² Division of Radiation Oncology, Department of Radiology, Faculty of Medicine, Chulalongkorn University, King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok, Thailand.
³ Section of Interventional Radiology, Department of Radiology, University of Washington School of Medicine, Seattle, Washington.

Abstract

Purpose: Data on the safety and efficacy of external beam radiation therapy (EBRT) after yttrium 90 transarterial radioembolization (TARE) for hepatocellular carcinoma (HCC) are limited. We report our experience using EBRT to treat HCC patients previously treated with TARE.

Methods and materials: We retrospectively analyzed 31 HCC patients who received EBRT following TARE. Eighteen (58%) were treated with photon therapy, and 13 (42%) with proton therapy. Eighteen patients (58%) had been previously treated with TARE within the EBRT-treated lesion, with a median total dose of 72 mCi (range, 49-272). Twenty-one patients (68%) had prior TARE outside the EBRT zone, with a median total dose of 84 mCi (range, 21-330). Toxicities and survival outcomes were analyzed.

Results: The number of prior TARE treatments ranged from 1 to 5: 14 patients (45%) received 1, and 17 (55%) received 2 or more. Indications for EBRT included incomplete TARE response (n = 2), technical TARE limitations (n = 25), and other reasons (n = 4). The median tumor size was 3.8 cm (range, 1.6-19.4). Most patients (87%) had a Child-Pugh (CP)-A score. With a median follow-up of 30 months, the 2-year progression-free survival and overall survival rates were 18% and 43%, respectively. The 2-year cumulative incidence of local failure was 7%. CP+2 progression was observed in 4 patients (13%). There was no significant difference in local failure or CP+2 rates based on the EBRT target location relative to prior TARE. Grade 3+ biliary complications occurred in 3 patients (10%): 2 biloma and 1 biliary stricture. All 3 patients had received at least 2 prior TARE treatments that overlapped with the area treated with EBRT and had tumors located near the central bile duct.

Conclusions: EBRT for HCC patients previously treated with yttrium 90 is feasible and offers excellent local control. Liver dysfunction and biliary toxicities are potential complications and should be weighed against the clinical benefits.